Though some of her brothers are away at college, Jack continues her life-long mission to prove that, even though she's a girl, she is as good as they are. Now in high school, her life is busy with playing the trombone and working at Doc's after school and on Saturdays. Never one to shy away from a challenge, Jack still manages to find the time to get herself smack in the middle of a mystery, and with her best friend Josh by her side, she jumps in with both feet. There has been an epidemic of pets poisoned in the neighborhood, including not only Thaddeus, her friend Dolores's dog, but also Mrs. Pete's cat, Cuddles. And then Jack's dog Trax is poisoned. Gravely concerned about the senseless cruelty to the neighborhood pets, Jack decides that the The Klingenhoeffer Agency's first case will be to find the Pet Executioner. In the midst of this horror, Trax brings home a dead domestic rabbit. Aghast at her dog's crime, she decides to cover up and gives the rabbit a bath and blow dries it's fur, so it looks almost as good as new. Now she just has to convince someone to help her sneak it back to its owner Through their shared detective work, Josh and Jack's friendship begins to blossom into something else. Josh must make a decision on whether he'll return to Minneapolis to be with his father, or stay with Jack. Jack's work with Doc brings about another new member of the family and more responsibilities. Can Jack juggle school, a detective agency, a pet killer and her changing relationship with Josh? One thing for sure, there's never a dull moment when Jack's involved